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Journal of Modern Physics 2015年第11期6卷 1679-1694页

作者： Néstor david Espinosa-Torres José álvaro david hernández de la luz José Francisco Javier Flores-Gracia José Alberto Luna-López Javier Martínez-Juárez Gregorio Flores-Carrasco IC-CIDS Benemérita Universidad Autónoma de Puebla Puebla México Ex Graduate Research Trainee at Plasma Processing laboratory Chemical Engineering Department McGill University Montreal Canada department of Materials Science and Engineering and Chemical Engineering University Carlos III of Madrid and IAAB Madrid Spain

The Global Reaction Model describes a set of chemical reactions that can potentially occur during the process of obtaining silicon rich oxide (SRO) films, regardless of the technique used to grow such films which are an outside stoichiometry material. Particularly, chemical reactions that occur during the process of growing of SRO films by LPCVD technique are highlighted in this model. We suggest and evaluate either some types of molecules or resulting nanostructures and we predict theoretically, by applying the density functional theory, the contribution that they may have to the phenomenon of luminescence which is measured in SRO films. Also, we have calculated the opto-electronic properties of SRO films. The suggested model provides enough information required to identify the molecular structures resulting from the presence of defects in SRO films and also those corresponding to charged structures. It is also possible to detect the molecular structures which are modified due to the effect of heat treatment, and identify the presence of different oxidation states inclusive the formation of siloxanes.

关键词： Global Reactions Model Silicon Rich-Oxide defects LPCVD Luminescence

<i>Ab Initio</i>Molecular Orbital Calculation for Optical and Electronic Properties Evaluation of Small and Medium Size Silicon Nano-Clusters Found in Silicon Rich Oxide Films

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Journal of Modern Physics 2013年第11期4卷 1-26页

作者： Néstor david Espinosa Torres José Francisco Javier Flores Gracia José Alberto Luna López Juan Carlos Ramírez García Alfredo Morales Sánchez José Luis Sosa Sánchez david hernández de la luz Francisco Morales Morales Research Center for Advanced Materials S.C. Unit Monterrey-PIIT Apodaca México Research Center for Semiconductor devices CIDS-ICUAP-BUAP Puebla México The Faculty of Chemical Sciences BUAP Puebla México

In systems in atomic and nano scales such as clusters or agglomerates constituted of particles from a few to less than one hundred of atoms, quantum confinement effects are very important. Their optical and electronic properties are often dependent on the size of the systems and the way in which the atoms in these clusters are bonded. Generally, these nano-structures display optical and electronic properties significantly different of those found in corresponding bulk materials. Silicon agglomerates found in Silicon Rich Oxide (SRO) films have optical properties, which have reported as depended directly on nano-crystal size. Furthermore, the room temperature photoluminescence (PL) of Silicon Rich Oxides (SRO) has repeatedly generated a huge interest due to their possible applications in optoelectronic devices. However, a plausible emission mechanism has not yet widespread acceptance of the scientific community. In this research, we employed the density Functional Theory with a functional B3LYP and a basis set 6 - 31G* to calculate the optical and electronic properties of small (six to ten silicon atoms) and medium size clusters of silicon (constituted of eleven to fourteen silicon atoms). With the theoretical calculation of the structural and optical properties of silicon clusters, it is possible to evaluate the contribution of silicon agglomerates in the luminescent emission mechanism experimentally found in thin SRO films.

关键词： Nano-Crystals Silicon Clusters Silicon-Rich Oxide Luminescence Magic-Number

Camalote Grass (Paspalum fasciculatum Willd) as a Sustainable Raw Material for the Production of Lignocellulosic Ethanol

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Journal of Sustainable Bioenergy Systems 2024年第2期14卷 23-33页

作者： María luz May-Reyes Cintya Valerio-Cárdenas Gloria Ivette Bolio-López Manuel Mateo hernández-Villegas Miguel Ángel Velázquez-Carmona Patricia de la Cruz-Burelo Research and Postgraduate Coordination Universidad Popular de la Chontalpa Crdenas Tabasco Mexico

The current trend of replacing a percentage of gasoline with ethanol has promoted the development of new processes for its production from lignocellulosic biomass. This work reports the production of ethanol from the Camalote grass (Paspalum fasciculatum Willd). The lignocellulosic biomass was subjected to acid hydrolysis at 125C and 15 psi with H2SO4 concentrations at 5%, 10%, and 20%, obtaining an average of reducing sugars (pentoses and hexoses) from the hydrolyzed juice with 12.3%, 10%, and 17% Brix, respectively. The sugars were fermented using yeast of the Saccharomyces cerevisiae at 30C for 48 hours. Finally, the ethanol was distilled at 78C, and the average yields were obtained through analysis of variance with a 95% confidence level. The values indicate that there is a significant difference (p > 0.05), the Tukey study shows that all the % v/v averages are different from each other. For H2SO4 concentration at 5% (10.33 ± 2), H2SO4 at 10% (9.33 ± 1.8), and H2SO4 at 20% (6.33 ± 2). The acidity analysis for the ethanol obtained from each treatment gave a value of 1.8 mg/L of acetic acid in all cases.

关键词： Lignocellulosic Ethanol Lignocellulosic Biomass Camalote Grass Acid Hydrolysis Energy Crops

Role of climatic variability in shaping intraspecific variation of thermal tolerance in Mediterranean water beetles

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Insect Science 2024年第1期31卷 285-298页

作者： Susana Pallarés david Garoffolo Belén Rodríguez david Sánchez-Fernández department of Zoology University of SevilleSevilleSpain Faculty of Biology Department of Ecology and HydrologyUniversity of MurciaCampus EspinardoMurciaSpain

The climatic variability hypothesis(CVH)predicts that organisms in more thermally variable environments have wider thermal breadths and higher thermal plasticity than those from more stable ***,due to evolutionary trade-offs,taxa with greater absolute thermal limits may have little plasticity of such limits(trade-off hypothesis).The CVH assumes that climatic variability is the ultimate driver of thermal tolerance variation across latitudinal and altitudinal gradients,but average temperature also varies along such *** explored intraspecific variation of thermal tolerance in three typical Mediterranean saline water beetles(families Hydrophilidae and Dytiscidae).For each species,we compared two populations where the species coexist,with similar annual mean temperature but contrasting thermal variability(continental *** population).We estimated thermal limits of adults from each population,previously acclimated at 17,20,or 25℃.We found species-specific patterns but overall,our results agree with the CVH regarding thermal ranges,which were wider in the continental(more variable)*** the two hydrophilid species,this came at the cost of losing plasticity of the upper thermal limit in this population,supporting the trade-off hypothesis,but not in the dytiscid *** results support the role of local adaptation to thermal variability and trade-offs between basal tolerance and physiological plasticity in shaping thermal tolerance in aquatic ectotherms,but also suggest that intraspecific variation of thermal tolerance does not fit a general pattern among aquatic *** such intraspecific variation could lead to inaccurate predictions of the vulnerability of aquatic insects to global warming.

关键词： acclimation capacity aquatic insects climate change heat coma temperature supercooling point thermal plasticity

Low-power SiPM readout BETA ASIC for space applications

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Nuclear Science and Techniques 2024年第3期35卷 153-169页

作者： Anand Sanmukh Sergio Gómez Albert Comerma Joan Mauricio Rafel Manera Andreu Sanuy Daniel Guberman Roger Catala Albert Espinya Marina Orta Oscar de la Torre david Gascon departament de Física Quàntica i Astrofísica(FQA) Institut de Ciències del Cosmos(ICCUB)Universitat de Barcelona(UB)08028 BarcelonaSpain Institut d’Estudis Espacials de Catalunya(IEEC) 08034 BarcelonaSpain Electronics department Serra Hunter fellow at Polytechnic University of Catalonia(UPC)08019 BarcelonaSpain

The BETA application-specific integrated circuit(ASIC)is a fully programmable chip designed to amplify,shape and digitize the signal of up to 64 Silicon photomultiplier(SiPM)channels,with a power consumption of approximately~1 mW/*** to its dual-path gain,the BETA chip is capable of resolving single photoelectrons(phes)with a signal-to-noise ratio(SNR)>5 while simultaneously achieving a dynamic range of~4000 ***,BETA can provide a cost-effective solution for the readout of SiPMs in space missions and other applications with a maximum rate below 10 *** this study,we describe the key characteristics of the BETA ASIC and present an evaluation of the performance of its 16-channel version,which is implemented using 130 nm *** ASIC also contains two discriminators that can provide trigger signals with a time jitter down to 400 ps FWHM for 10 *** linearity error of the charge gain measurement was less than 2%for a dynamic range as large as 15 bits.

关键词： Radiation detectors Silicon photomultipliers Photon sensors Front-end electronics Mixed-mode ASICs Space technology

Towards an integrated risk analysis security framework according to a systematic analysis of existing proposals

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Frontiers of Computer Science 2024年第3期18卷 199-216页

作者： Antonio SANTOS-OLMO Luis Enrique SÁNCHEZ david G.ROSADO Manuel A.SERRANO Carlos BlaNCO Haralambos MOURATIDIS Eduardo FERNÁndez-MEDINA GSyA Research Group University of Castilla-La ManchaCiudad Real 13071Spain Institute for Analytics and Data Science University of EssexColchester CO43SQUK Alarcos Research Group University of Castilla-La ManchaCiudad Real 13071Spain ISTR Research group Department of Computer Science and ElectronicsUniversity of CantabriaSantander 39005Spain

The information society depends increasingly on risk assessment and management systems as means to adequately protect its key information *** availability of these systems is now vital for the protection and evolution of ***,several factors have led to an increasing need for more accurate risk analysis *** are:the speed at which technologies evolve,their global impact and the growing requirement for companies to *** analysis processes must consequently adapt to these new circumstances and new technological *** objective of this paper is,therefore,to present the results of an exhaustive analysis of the techniques and methods offered by the scientific community with the aim of identifying their main weaknesses and providing a new risk assessment and management *** analysis was carried out using the systematic review protocol and found that these proposals do not fully meet these new *** paper also presents a summary of MARISMA,the risk analysis and management framework designed by our research *** basis of our framework is the main existing risk standards and proposals,and it seeks to address the weaknesses found in these *** is in a process of continuous improvement,as is being applied by customers in several European and American *** consists of a risk data management module,a methodology for its systematic application and a tool that automates the process.

关键词： information security management security system security risk assessment and management

Instance Segmentation of Characters Recognized in Palmyrene Aramaic Inscriptions

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Computer Modeling in Engineering & Sciences 2024年第9期140卷 2869-2889页

作者： Adéla Hamplová Alexey Lyavdansky TomášNovák Ondrej Svojše david Franc Arnošt Veselý Czech University of Life Sciences in Prague(CULS) Faculty of Economics and ManagementDepartment of Information EngineeringPrague16500Czech Republic National Research University Higher School of Economics(HSE) Faculty of HumanitiesInstitute for Oriental and Classical StudiesMoscow101000The Russian Federation

This study presents a single-class and multi-class instance segmentation approach applied to ancient Palmyrene inscriptions,employing two state-of-the-art deep learning algorithms,namely YOLOv8 and Roboflow *** goal is to contribute to the preservation and understanding of historical texts,showcasing the potential of modern deep learning methods in archaeological *** research culminates in several key findings and scientific *** comprehensively compare the performance of YOLOv8 and Roboflow 3.0 in the context of Palmyrene character segmentation—this comparative analysis mainly focuses on the strengths and weaknesses of each algorithm in this *** also created and annotated an extensive dataset of Palmyrene inscriptions,a crucial resource for further research in the *** dataset serves for training and evaluating the segmentation *** employ comparative evaluation metrics to quantitatively assess the segmentation results,ensuring the reliability and reproducibility of our findings and we present custom visualization tools for predicted segmentation *** study advances the state of the art in semi-automatic reading of Palmyrene inscriptions and establishes a benchmark for future *** availability of the Palmyrene dataset and the insights into algorithm performance contribute to the broader understanding of historical text analysis.

关键词： Optical character recognition instance segmentation Palmyrene ancient languages computer vision

Intense pulsed light‑based treatment for the improvement of symptoms in glaucoma patients treated with hypotensive eye drops

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Eye and Vision 2024年第2期10卷 12-21页

作者： Jose Maria Martinez‑de‑la‑Casa Carlos Oribio‑Quinto Almudena Milans‑del‑Bosch Pilar Perez‑Garcia laura Morales‑Fernandez Javier Garcia‑Bella Jose Manuel Benitez‑del‑Castillo Julian Garcia‑Feijoo david P.Pinero Ophthalmology Unit Department of Ophthalmology and ORLFaculty of MedicineHospital Clinico San-CarlosUniversidad Complutense de MadridInstituto de Investigacion Sanitaria del Hospital Clinico San-Carlos(IdISSC)28040 MadridSpain department of Immunology Ophthalmology and ORLSchool of MedicineInstituto de Investigaciones Oftalmologicas Ramon CastroviejoUniversidad Complutense de MadridMadridSpain department of Optics Pharmacology and AnatomyUniversity of AlicanteAlicanteSpain

Background:Ocular surface disease in glaucoma patients is a significant ocular co-morbidity that can affect 40%to 59%of these patients *** current study was aimed at evaluating the potential clinical benefit of an intense pulsed light(IPL)-based treatment in glaucomatous patients with ocular surface disease due to prolonged hypotensive eyedrop *** our knowledge,this is the first series analyzing the therapeutic effect of this treatment option in this type of ***:This non-comparative prospective case series study enrolled a total of 30 glaucoma patients ranging in age from 57 to 94 years old and treated with hypotensive eyedrops for years with dry eye *** patients received four sessions of IPL treatment using the Optima IPL system(Lumenis,Yokneam,Israel)adjusted to the official optimized Lumenis *** in symptomatology,corneal staining,conjunctival hyperemia,non-invasive break-up time(NIBUT),tear osmolarity,tear meniscus height(TMH),meiboscore and meibomian gland expressibility was analyzed after ***:Statistically significant reductions were observed after IPL treatment in the symptomatology scores measured with different questionnaires[ocular surface disease index(OSDI),standard patient evaluation of eye dryness(SPEED)and symptom assessment questionnaire in dry eye(SANde)]as well as with the visual analogue scale(Plarity(P=0.001).A significant reduction was also found in meibomian gland expressibility(P=0.003),changing the percentage of grade 3 eyes from 44.4%before IPL to 17.2%after ***:IPL therapy combined with meibomian gland expression(MGX)seems to be an effective option to improve symptomatology in glaucomatous patients with ocular surface diseas

关键词： Glaucoma Intense pulsed light Dry eye Meibomian glands

design and Sizing of an Ecological Wastewater Treatment System in a School Environment: A Case Study of Ndiebene Gandiol 1 School

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Journal of Water Resource and Protection 2024年第1期16卷 41-57页

作者： Falilou Coundoul Abdou Khafor Ndiaye Abdoulaye deme david de la Varga Polytechnic Institute of Saint-Louis Gaston Berger University Saint-Louis Senegal Applied Sciences and Technologies Training and Research Unit Gaston Berger University Saint-Louis Senegal laboratory of Chemical-Physical and Chemical Engineering I University of A Coru&ntildea A Coru&ntildea Spain

The primary objective of this study was to design and size a sustainable sanitation solution for the Ndiebene Gandiol 1 school located in the eponymous commune in northern Senegal. Field investigations led to the collection of wastewater samples. Their analysis revealed specific pollutant loads, including loads of BOD5 3.6966 kgO2/day and COD of 12.8775 kgO2/day, which were central to the design phase. Following a rigorous assessment of the existing sanitation infrastructure, constructed wetland (CWs) emerged as the most appropriate ecological solution. This system, valued for its ability to effectively remove contaminants, was tailored to the specific needs of the site. Consequently, the final design of the filter extends over 217.16 m2, divided into two cells of 108.58 m2 each, with dimensions of 12.77 m in length and 8.5 m in width. The depth of the filtering medium is approximately 0.60 m, meeting the standards while ensuring maximized purification. Typha, an indigenous and prolific plant known for its purification abilities, was selected as the filtering agent. Concurrently, non-crushed gravel was chosen for its proven filtration capacity. This study is the result of a combination of scientific rigor and design expertise. It provides a holistic view of sanitation for Ndiebene Gandiol. The technical specifications and dimensions of the constructed wetland filter embody an approach that marries indepth analysis and practical application, all aimed at delivering an effective and long-lasting solution to the local sanitation challenges. By integrating precise scientific data with sanitation design expertise, this study delivers a holistic solution for Ndiebene Gandiol. The detailed dimensions and specifications of the constructed wetland filter reflect a methodology that combines meticulous analysis with practical adaptation, aiming to provide an effective and sustainable response to the challenges of rural and school san

关键词： Water Review Hydraulic Engineering Water Treatment Agricultural Irrigation Sanitation Engineering Environment

A Tutorial on Federated Learning from Theory to Practice:Foundations,Software Frameworks,Exemplary Use Cases,and Selected Trends

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IEEE/CAA Journal of Automatica Sinica 2024年第4期11卷 824-850页

作者： M.Victoria luzón Nuria Rodríguez-Barroso Alberto Argente-Garrido Daniel Jiménez-López Jose M.Moyano Javier del Ser Weiping Ding Francisco Herrera department of Software Engineering Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain department of Computer Science and Artificial Intelligence Andalusian Research Institute in Data Science and Computational Intelligence(DaSCI)University of GranadaGranada 18071Spain department of Communications Engineering University of the Basque Country(UPV/EHU)and also with TECNALIABasque Research&Technology Alliance(BRTA)Spain School of Information Science and Technology Nantong UniversityNantong 226019China

When data privacy is imposed as a necessity,Federated learning(FL)emerges as a relevant artificial intelligence field for developing machine learning(ML)models in a distributed and decentralized *** allows ML models to be trained on local devices without any need for centralized data transfer,thereby reducing both the exposure of sensitive data and the possibility of data interception by malicious third *** paradigm has gained momentum in the last few years,spurred by the plethora of real-world applications that have leveraged its ability to improve the efficiency of distributed learning and to accommodate numerous participants with their data *** virtue of FL,models can be learned from all such distributed data sources while preserving data *** aim of this paper is to provide a practical tutorial on FL,including a short methodology and a systematic analysis of existing software ***,our tutorial provides exemplary cases of study from three complementary perspectives:i)Foundations of FL,describing the main components of FL,from key elements to FL categories;ii)Implementation guidelines and exemplary cases of study,by systematically examining the functionalities provided by existing software frameworks for FL deployment,devising a methodology to design a FL scenario,and providing exemplary cases of study with source code for different ML approaches;and iii)Trends,shortly reviewing a non-exhaustive list of research directions that are under active investigation in the current FL *** ultimate purpose of this work is to establish itself as a referential work for researchers,developers,and data scientists willing to explore the capabilities of FL in practical applications.

关键词： Data privacy distributed machine learning federated learning software frameworks